Calcium and collagen regulator, osteoporosis. Perturbations in calcareous tissues; neoplasms of bone; exostosis, periostosis; pathological conditions of the skeletal (osteogenic) system: osteoporosis, osteomalacia, rickets, fragility of the bones; inflammatory conditions of bone including: coxitis, osteoarthritis, periostitis; hernation of the nucleus pulposus.